Schottky barrier and contact resistance of InSb nanowire field effect transistors

• Published in: arXiv.org
• Main Authors: Fan, Dingxun, Kang, N, Sepideh Gorji Ghalamestani, Dick, Kimberly A, Xu, H Q
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 27.05.2016
• Subjects: Contact resistance; Electric contacts; Field effect transistors; Gold; Indium antimonide; Intermetallic compounds; Magnetic fields; Nanoelectronics; Nanotechnology devices; Nanowires; Physics - Mesoscale and Nanoscale Physics; Semiconductor devices; Titanium; Transistors
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1605.08689

Understanding of the electrical contact properties of semiconductor nanowire (NW) field effect transistors (FETs) plays a crucial role in employing semiconducting NWs as building blocks for future nanoelectronic devices and in the study of fundamental physics problems. Here, we report on a study of the contact properties of Ti/Au, a widely used contact metal combination, to individual InSb NWs via both two-probe and four-probe transport measurements. We show that a Schottky barrier of height \(\Phi_{\rm{SB}}\sim20\ \rm{meV}\) is present at the metal-InSb NW interfaces and its effective height is gate tunable. The contact resistance (\(R_{\rm{c}}\)) in the InSb NWFETs is also analyzed by magnetotransport measurements at low temperatures. It is found that \(R_{\rm{c}}\) at on-state exhibits a pronounced magnetic field dependent feature, namely it is increased strongly with increasing magnetic field after an onset field \(B_{\rm{c}}\). A qualitative picture that takes into account magnetic depopulation of subbands in the NWs is provided to explain the observation. Our results provide a solid experimental evidence for the presence of a Schottky barrier at Ti/Au-InSb NW interfaces and can be used as a basis for design and fabrication of novel InSb NW based nanoelectronic devices and quantum devices.